A low foaming nonionic surfactant would have many industrial applications where prior art nonionic surfactants cannot be used. Past efforts to create a low foaming nonionic surfactant have proved largely unsucessful.
Prior art nonionic surfactants are predominately ethylene oxide adducts of detergent range alcohols, about C.sub.8 to about C.sub.18 alcohols, or alkyl phenols which possess high foaming characteristics. Other alcohols having fewer carbon atoms have heretofore been useful largely as functional fluids and the like while possessing little, if any, surface active properties. We have discovered that foaming and detergent characteristics and viscosity characteristics of monohydroxyl or monocarboxyl aliphatic compounds can be varied by reaction, in certain proportions, with alkylene carbonates or with an alkylene oxide and carbon dioxide to provide novel compounds having different and unexpected properties.
The general reaction procedures for preparing the polyether polycarbonate materials are described by Stevens in U.S. Pat. Nos. 3,248,414; 3,248,415; and 3,248,416 which teach the preparation of polyether polycarbonates from carbon dioxide and alkylene oxide; (2) alkylene carbonate; and (3) alkylene carbonate and alkylene oxide. According to the described method, a minor amount of polyfunctional initiator such as between 0.005 to about 0.2 moles of a polyhydric initiator per mole of alkylene oxide or alkylene carbonate is employed. The reactions are conducted under superatmospheric pressure in the presence of a metal oxide, metal carbonate, trisodium phosphate or tertiary amine catalyst to produce high molecular weight polyether polycarbonates wherein the polyfunctional initiator is incorporated internally to the polymer.
These polyfunctional polycarbonates are generally viscous, syrupy liquids or waxy solids and are taught to be useful for reaction with other polyfunctional materials such as polyisocyantes to form various polymers. A primary use has been the reaction with dicarboxylic acids to produce valuable and highly useful alkyd resins.
The catalysts employed in the polycarbonate reaction are well described in Maximovich, U.S. Pat. Nos. 3,689,462 and 3,896,090 which teach the use of a metal stannate catalyst such as potassium stannate and titanate, tetraborate and metaborate catalyst to prepare polyether polycarbonates according to the methods disclosed by Stevens.
While the methods of preparing polyether polycarbonates and the applicability of such materials for the formation of other useful polymers is well known, no one has heretofore recognized the usefulness of monofunctional polycarbonate materials. Until now the applicability of the reaction to produce a new class of surface active agents and functional fluids has been totally unrecognized.